What is polymorphism?

What is polymorphism?

• A. Individuals in the population have different sequences of nucleotides in their DNA
• B. A mutation that occurs in somatic cells
• C. An enzyme that repairs DNA
• D. A chromosomal rearrangement

Answer: (A)

Polymorphism means genetic variation among individuals within a population, with more than one allele or DNA sequence present at a given locus at appreciable frequency. This is exactly captured by saying that individuals in the population have different sequences of nucleotides in their DNA. Such variation is heritable and provides the raw material for natural selection and breeding decisions, helping populations adapt over time. The other descriptions describe processes or features that aren’t population-wide DNA sequence variation: a somatic mutation occurs in body cells and isn’t passed to offspring, an enzyme that repairs DNA is a protein with a specific function, and a chromosomal rearrangement is a structural change that isn’t by itself the definition of polymorphism.

Polymorphism means genetic variation among individuals within a population, with more than one allele or DNA sequence present at a given locus at appreciable frequency. This is exactly captured by saying that individuals in the population have different sequences of nucleotides in their DNA. Such variation is heritable and provides the raw material for natural selection and breeding decisions, helping populations adapt over time. The other descriptions describe processes or features that aren’t population-wide DNA sequence variation: a somatic mutation occurs in body cells and isn’t passed to offspring, an enzyme that repairs DNA is a protein with a specific function, and a chromosomal rearrangement is a structural change that isn’t by itself the definition of polymorphism.